Answer:
0.006 48 km/s
Explanation:
1. Convert miles to kilometres
14.5 mi × (1.609 km/1 mi) = 23.33 km
2. Convert hours to seconds
1 h × (60 min/1h) × (60 s/1 min) = 3600 s
3. Divide the distance by the time
14.5 mi/1 h = 23.3 km/3600 s = 0.006 48 km/s
Answer:
1 strong acid
2 yes they are dangerous
Explanation:
Since nearly all of it is dissociated in water, it is called a strong acid.
2 yes Concentrated strong acids can cause severe and painful burns. The pain is due in part to the formation of a protein layer, which resists further penetration of the acid
Explanation:
Since HF is a weak acid, the use of an ICE table is required to find the pH. The question gives us the concentration of the HF.
HF+H2O⇌H3O++F−HF+H2O⇌H3O++F−
Initial0.3 M-0 M0 MChange- X-+ X+XEquilibrium0.3 - X-X MX M
Writing the information from the ICE Table in Equation form yields
6.6×10−4=x20.3−x6.6×10−4=x20.3−x
Manipulating the equation to get everything on one side yields
0=x2+6.6×10−4x−1.98×10−40=x2+6.6×10−4x−1.98×10−4
Now this information is plugged into the quadratic formula to give
x=−6.6×10−4±(6.6×10−4)2−4(1)(−1.98×10−4)−−−−−−−−−−−−−−−−−−−−−−−−−−−−√2x=−6.6×10−4±(6.6×10−4)2−4(1)(−1.98×10−4)2
The quadratic formula yields that x=0.013745 and x=-0.014405
However we can rule out x=-0.014405 because there cannot be negative concentrations. Therefore to get the pH we plug the concentration of H3O+ into the equation pH=-log(0.013745) and get pH=1.86
What element has the same number of orbits as Hydrogen? Why? Do they have similar properties, why?
Answer:
Helium
Explanation:
Helium has the same number of orbitals as hydrogen because they belong to the same period on the periodic table.
Periods are the horizontal arrangement of elements. Elements in the same period are known to have the same number of electronic shell or orbitals.
In period 1 where we have just Hydrogen and Helium, the number of orbitals is 1.
For properties of a specie, elements in the same group which are the vertical arrangement of elements have the same properties. Since both Hydrogen and helium are in different groups, their properties differ.
